Photomask blank



FIG. 1 is a front elevation view of a second embodiment of the photoask blank showing our new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is an enlarged partial front view along line 7—7 in FIG. 10;

FIG. 8 is a reduced scale front, left side, top perspective view of the portion shown in FIG. 7 ;

FIG. 9 is a sectional view along line 9—9 in FIG. 7.

The broken line showing is for illustrative purposes only and forms no part of the claimed design.

FIG. 10 is a front elevation view of a second embodiment of the photomask blank shown in FIG. 1;

FIG. 11 is a rear elevational view thereof;

FIG. 12 is a left side view thereof;

FIG. 13 is a right side view thereof;

FIG. 14 is a top plan view thereof;

FIG. 15 is a bottom plan view thereof;

FIG. 16 is an enlarged partial front view along line 16-16 in FIG. 10;

FIG 17 is a reduced scale front, left side, top perspective view of the portion shown in FIG. 16; and,

FIG. 18 is a sectional view along line 18-18 in FIG. 16. 

The ornamental design for a photomask blank, as shown and described. 